Types of Appliances

There are various types of fixed and removable orthodontic appliances that are used in conjunction with orthodontic treatment.  Below are a list of the most popular ones.

Expanders or Expansion Appliances

Expanders can be used for both the upper and lower jaws but the most common type is the palatal or upper jaw expander.  Palatal expansion improves the way the upper and lower jaws and the upper and lower teeth work together.  It widens the jaw so there is sufficient room for the permanent upper and lower teeth to come in and can be used in the correction of crossbites.  A narrow palate, if left untreated, may not allow enough room for the permanent teeth to come in and could lead to excessive wearing of the teeth or the need for extensive dental work as an adult.  Expansion can take a few weeks to a few months and is dependent on the amount of expansion required.  Expansion can make the final smile broader and more attractive.


Mouthguards are removable plastic or rubber appliances that fit over the teeth to protect them during sports.  Mouthguards or mouth protectors help to cushion a blow to the face minimizing the risk of broken teeth and injuries to the lips, tongue, face or jaw.  They typically cover the upper teeth.  Mouthguards are especially important for people who wear braces.  A blow to the face could damage the brackets or other fixed orthodontic appliances.  A mouthguard also provides a barrier between the braces and cheek or lips limiting the risk of soft tissue injuries.

Another form of a mouth guard is a night guard or splint.  It is usually worn by a person who tends to grind or brux their teeth at night.  A night guard is worn to minimize the detrimental effects of grinding and clenching.

Habit Appliances

There are several kinds of habit appliances such as thumb sucking appliances or tongue cribs that help reduce or eliminate the harmful effects of sucking a finger or of an overactive tongue.  Strong thumb sucking can make the front teeth move and even reshape the jaw bones causing the upper front teeth to flare while the lower front teeth move back and inward.  Severe habits can create an open bite.  An overactive tongue can also create a space between the front teeth or jaws.


Headgears are removable appliances that are generally worn at night that can help move upper teeth and restrict the growth of the upper jaw.  It generally consists of a facebow that attaches to the teeth along with a strap that fits around the head or neck.  Headgears are rarely used today with the advent of other forms of orthodontic tooth movement.


Retainers are worn after the braces are removed to preserve and stabilize the results achieved during orthodontic treatment.  Retainers are used for two reasons.  They allow the bone to rebuild after the teeth have moved and they help keep the individual teeth from drifting.  There are many types and designs of both upper and lower retainers.  Some are removable, the kind you take in and out, while others are fixed or bonded behind the teeth.  Retainers do not always eliminate shifting completely.  There are many reasons teeth may move following orthodontic treatment.  Teeth are set in bone and the bone around the teeth is continually changing (breaking down and rebuilding).  Teeth may shift after the braces are removed.  Changes in tooth position are a lifelong and naturally occuring phenomenon.

Spacers or Separators

Spacers or separators are little elastics or clips that go between the teeth to create a small amount of room so that appliances or bands can be placed.